Search results for " surface"
showing 10 items of 2838 documents
Tear <sup>1</sup>H Nuclear Magnetic Resonance-Based Metabolomics Application to the Molecular Diagnosis of Aqueous Tear Deficiency and Me…
2020
<b><i>Purpose:</i></b> Meibomian gland dysfunction (MGD) is a major cause of signs and symptoms related to dry eyes (DE) and eyelid inflammation. We investigated the composition of human tears by metabolomic approaches in patients with aqueous tear deficiency and MGD. <b><i>Methods:</i></b> Participants in this prospective, case-control pilot study were split into patients with aqueous tear deficiency and MGD (DE-MGD [<i>n</i> = 15]) and healthy controls (CG; <i>n</i> = 20). Personal interviews, ocular surface disease index (OSDI), and ophthalmic examinations were performed. Reflex tears collected by capillarity were pr…
Theory of mercury intrusion in a distribution of unconnected wedge-shaped slits
2004
Effective mercury intrusion in a wedge-shaped slit is gradual, the intruded depth increasing with applied pressure. The Washburn equation must be modified accordingly. It relates the distance, e, separating the three-phase contact lines on the wedge faces to the hydrostatic pressure, P, wedge half-opening angle alpha, mercury surface tension gamma, and contact angle theta: e=(-2gamma/P)cos(theta-alpha) if theta-alpha>pi2. The equations relating the volume of mercury in a single slit to hydrostatic pressure are established. The total volume of mercury V(Hg)(tot)(E(0),e) intruded in a set of unconnected isomorphous slits (same alpha value) with opening width, E, distributed over interval [E(0…
Comparison of the effect of different medicaments on surface reproduction of two commercially available Polyvinyl Siloxane impression materials - An …
2013
Objective:To determine the effect of different retraction cord medicaments on surface detail reproduction of polyvinyl siloxane impression materials and compare this effect on any two brands of commercially available polyvinyl siloxane impression materials. Material and methods: Four stainless steel dies were made according to ADA specification no.19. Three dies were treated with aluminium chloride (5%), ferric sulphate (13.3%) and epinephrine (0.1%) while the fourth one was left untreated to serve as control. Two impression materials (Dentsply and 3M ESPE) were used. Results: All the three medicaments adversely affected the surface detail reproduction of both the brands of the polyvinyl si…
CAROLS campaigns 2009: First Results
2010
International audience; The CAROLS, L band radiometer, is built and designed as a copy of EMIRAD II radiometer of DTU team. It is a Correlation radiometer with direct sampling and fully polarimetric (i.e 4 Stockes). It will be used in conjunction with other airborne instruments (in particular the C-Band scatterometer (STORM) and IEEEC GPS system, Infrared CIMEL radiometer and one visible camera), in coordination with in situ field campaigns for SMOS CAL/VAL. The instruments are implemented on board the French research airplane ATR42. A scientific campaign with thirteen flights is realized over south-western France, Valencia site and Bay of Biscay (Atlantic Ocean) in spring 2009. In order to…
2-Aminopurine non-radiative decay and emission in aqueous solution: A theoretical study
2008
Abstract The minimum energy path along the lowest-lying ππ ∗ excited state of 2-aminopurine was calculated to elucidate the mechanisms of radiationless decay and emission in water. The sequential Monte Carlo quantum mechanics approach with a multiconfigurational and perturbative description of the wave function was employed to compute the minimum, transition state, and conical intersection. It was found that the barrier in the potential energy surface to access the conical intersection funnel increases in aqueous environment, making the system prone to enlarge the emission yield. These results rationalize the observed enhancement of emission in 2-aminopurine upon increasing of the solvent p…
Measurements of pressure and frictional tractions along walls of a large-scale conical shallow hopper and comparison with Eurocode 1991-4:2006
2014
Abstract A silo׳s hopper supports the majority loads induced by the stored particulate solids. Such loads vary from filling to discharging provided the hopper is steep enough to secure a mass flow; when the hopper is too shallow to promote a mass flow, funnel flow usually prevails – where how loads develop along walls of a shallow hopper remains to be addressed. In the paper, normal pressure and frictional traction were measured with pressure transducers as imposed by testing material sand along the walls of a full-scale conical shallow hopper. The transducers were carefully mounted in the designated positions of hopper walls along a generator. To make the measurement results representative…
Carbons from second generation biomass as sustainable supports for catalytic systems
2018
Abstract In this study activated carbons were produced from the wood of three different wood species (pine, birch, spruce). The resulting activated carbons were characterized in bulk for ash content, carbon content (elemental analyses), specific surface area, and pore size distribution, and at the surface by measuring the autogenerated pH and studying their structure by XPS. All the samples presented high surface areas and appeared to be mesoporous materials (mesopores >80%). The carbons were then used as support for AuPt nanoparticles and tested in the liquid phase oxidation of glycerol (GLY) and in the hydrogenation of levulinic acid (LA), two important chemicals from cellulose-based biom…
Reversible self-assembly of metal chalcogenide/metal oxide nanostructures based on Pearson hardness.
2010
Nanotechnology has reached a stage of development where not individual nanoparticles but rather systems of greater complexity are the focus of concern. These complex structures incorporate two or more types of materials, an example of which is the formation of metal–semiconductor hybrids, which effectively combine the properties of both materials. The assembly of multicomponent nanoparticles from constituents with different optical, electrical, magnetic, and chemical properties can lead to novel functionalities that are independent of the individual components and may be tailored to fit a specific application. These applications include such far-reaching challenges as solar energy conversio…
MODIFICA SUPERFICIALE DI FILM DI POLY(ETILENE-co-ACIDO ACRILICO) CON NANOPARTICELLE DI SILICE ATTIVATA
2009
Coordination chemistry on surfaces through vapor phase processing: smart molecular/graphene heterostructures based on spin-crossover complexes and 2D…
2023
Los compuestos de coordinación están últimamente focalizando la atención de los investigadores en el campo de la nanociencia. Particular interés están generando aquellos compuestos con propiedades magnéticas de cara a su integración a la nanoescala en ramas como la electrónica y/o la espintrónica moleculares. Sin embargo, para su uso real en dispositivos destinados a estas aplicaciones, su procesabilidad es un requisito indispensable. En el marco de esta necesidad, la presente tesis doctoral se ha destinado al estudio del procesado sobre superficies mediante técnicas de fase gas de dos tipos distintos de compuestos de coordinación. Por tanto, el trabajo se ha dividido en dos partes. La prim…